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                            <div style="color:gray; word-break: break-all; font-size:12px;">原英文版地址: <a href="https://www.elastic.co/guide/en/elasticsearch/reference/7.7/remote-recovery.html" rel="nofollow" target="_blank">https://www.elastic.co/guide/en/elasticsearch/reference/7.7/remote-recovery.html</a>, 原文档版权归 www.elastic.co 所有<br/>本地英文版地址: <a href="../en/remote-recovery.html" rel="nofollow" target="_blank">../en/remote-recovery.html</a></div>
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<strong>重要</strong>: 此版本不会发布额外的bug修复或文档更新。最新信息请参考 <a href="https://www.elastic.co/guide/en/elasticsearch/reference/current/index.html" rel="nofollow">当前版本文档</a>。
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<a id="remote-recovery"></a>Remote recovery<a class="edit_me edit_me_private" rel="nofollow" title="Editing on GitHub is available to Elastic" href="https://github.com/elastic/elasticsearch/edit/7.7/docs/reference/ccr/remote-recovery.asciidoc">edit</a><a class="xpack_tag" href="https://www.elastic.co/subscriptions"></a>
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<p>When you create a follower index, you cannot use it until it is fully initialized.
The <em>remote recovery</em> process builds a new copy of a shard on a follower node by
copying data from the primary shard in the leader cluster. Elasticsearch uses this remote
recovery process to bootstrap a follower index using the data from the leader index.
This process provides the follower with a copy of the current state of the leader index,
even if a complete history of changes is not available on the leader due to Lucene
segment merging.</p>
<p>Remote recovery is a network intensive process that transfers all of the Lucene
segment files from the leader cluster to the follower cluster. The follower
requests that a recovery session be initiated on the primary shard in the leader
cluster. The follower then requests file chunks concurrently from the leader. By
default, the process concurrently requests <code class="literal">5</code> large <code class="literal">1mb</code> file chunks. This default
behavior is designed to support leader and follower clusters with high network latency
between them.</p>
<p>There are dynamic settings that you can use to rate-limit the transmitted data
and manage the resources consumed by remote recoveries. See
<a href="ccr-settings.html" class="ulink" target="_top">Cross-cluster replication settings</a>.</p>
<p>You can obtain information about an in-progress remote recovery by using the
<a href="cat-recovery.html" class="ulink" target="_top">recovery API</a> on the follower cluster. Remote recoveries
are implemented using the <a href="modules-snapshots.html" class="ulink" target="_top">snapshot and restore</a> infrastructure. This means that on-going remote recoveries are labelled as type
<code class="literal">snapshot</code> in the recovery API.</p>
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